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1. Reimagining e⁺e⁻ collider precision luminosity measurements

   https://doi.org/10.1051/epjconf/202431501024  

   Wilson, Graham; Madison, Brendon (December 2024, EPJ Web of Conferences)

   Jeans, D; Tian, J (Ed.)

   Our recent work has shown that a novel much higher granularity forward calorimetry concept can enable much more detailed and precise reconstruction than the baseline designs based on LEP luminometers, along with the capability of electron/positron/photon separation. This new calorimeter concept is designed primarily to maximize the acceptance for e⁺e⁻→ γγ as an alternative luminosity process, where it serves to define the inner edge of the acceptance (there is no outer edge, as the complete detector is used in the measurement), while continuing to provide the standard luminosity measurement from small-angle Bhabha scattering (SABS). It will also serve as a general forward electromagnetic calorimeter helping ensure hermeticity and detecting individual electrons, positrons, and photons. In this contribution we highlight the Bhabha rejection capability in the context of the e⁺e⁻→ γγ luminosity measurement and motivate the utility of a Bhabha “mini-tracker” consisting of a few planes of upstream thin silicon detectors. This could further refine the e⁺/e⁻polar angle measurement, aid with charge measurement, improve Bhabha rejection (for γγ), and, last-but-not-least, help mitigate the beam-induced electromagnetic deflection that biases the Bhabha acceptance by providing high precision longitudinal vertex information in Bhabha events, which can be used to diagnose this effect of the beam on the final-state electron and positron. 

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2. Discrete Brush Polymers Enhance ¹⁹ F MRI Performance through Architectural Precision

   https://doi.org/10.1021/jacs.5c00938  

   Ogbonna, Nduka_D; Guragain, Parikshit; Mayandi, Venkatesh; Sadrinia, Cyrus; Danrad, Raman; Jois, Seetharama; Lawrence, Jimmy (May 2025, Journal of the American Chemical Society)
3. Study of the ⁴⁴ Ti(α, p) ⁴⁷ V reaction rate using high-precision ⁵⁰ Cr(p, t) ⁴⁸ Cr measurements

   https://doi.org/10.1088/1742-6596/2586/1/012106  

   Binda, S D; Adsley, P; Long, A M; Berg, G; Brümmer, J W; Couder, M; Görres, J; Kamimota, M; Khumalo, N; Köhne, M; et al (September 2023, Journal of Physics: Conference Series)

   Abstract The abundance and distribution of⁴⁴Ti tells us about the nature of the core-collapse supernovae explosions. There is a need to understand the nuclear reaction network creating and destroying⁴⁴Ti in order to use it as a probe for the explosive mechanism. The⁴⁴Ti(α, p)⁴⁷V reaction is a very important reaction and it controls the destruction of⁴⁴Ti. Difficulties with direct measurements have led to an attempt to study this reaction indirectly. Here, the first step of the indirect study which is the identification of levels of the compound nucleus⁴⁸Cr is presented. A 100-MeV proton beam was incident on a⁵⁰Cr target. States in⁴⁸Cr were populated in the⁵⁰Cr(p, t)⁴⁸Cr reaction. The tritons were momentum-analysed in the K600 Q2D magnetic spectrometer at iThemba LABS. 

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4. Invariance of the r ² -ln(F) relationship and attainable precision in ultrafast laser ablation experiments

   https://doi.org/10.1364/OE.418288  

   Zhou, Boyang; Kar, Aravinda; Soileau, M_J; Yu, Xiaoming (February 2021, Optics Express)

   Pursuing ever-smaller feature size in laser-based lithography is a research topic of vital importance to keep this technique competitive with other micro-/nano-fabrication methods. Features smaller than the diffraction-limited spot size can be obtained by “thresholding”, which utilizes the deterministic nature of damage threshold with ultrashort laser pulses and is achieved by precisely tuning pulse energies so that only the central portion of the focal spot produces permanent modification. In this paper, we examine the formulation commonly used to describe thresholding and show that the relationship between feature size (r) and laser fluence (F) is invariant with respect to the nature of laser absorption. Verified by our experiments performed on metal, semiconductor, and dielectric samples, such invariance is used to predict the smallest feature size that can be achieved for different materials in a real-world system. 

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5. Phosphorescence in Mn ⁴⁺ -Doped R ⁺ / R ²⁺ Germanates ( R ⁺ = Na ⁺ or K ⁺ , R ²⁺ = Sr ²⁺ )

   https://doi.org/10.1021/acs.inorgchem.2c01364  

   Novikov, Sergei A.; Lu, Yimin; Zhang, Weiguo; Halasyamani, P. Shiv; Hariyani, Shruti; Brgoch, Jakoah; Klepov, Vladislav V.; zur Loye, Hans-Conrad; Mozharivskyj, Yurij (June 2022, Inorganic Chemistry)